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          --- old/src/share/vm/runtime/arguments.cpp
          +++ new/src/share/vm/runtime/arguments.cpp
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2516 2516        // are occasions when there's lots of live data in the young gen
2517 2517        // and we end up promoting some of it.  We don't have a definite
2518 2518        // explanation for why bumping OldPLABSize helps, but the theory
2519 2519        // is that a bigger PLAB results in retaining something like the
2520 2520        // original allocation order after promotion, which improves mutator
2521 2521        // locality.  A minor effect may be that larger PLABs reduce the
2522 2522        // number of PLAB allocation events during gc.  The value of 8kw
2523 2523        // was arrived at by experimenting with specjbb.
2524 2524        FLAG_SET_CMDLINE(uintx, OldPLABSize, 8*K);  // Note: this is in words
2525 2525  
2526      -      // CompilationPolicyChoice=0 causes the server compiler to adopt
2527      -      // a more conservative which-method-do-I-compile policy when one
2528      -      // of the counters maintained by the interpreter trips.  The
2529      -      // result is reduced startup time and improved specjbb and
2530      -      // alacrity performance.  Zero is the default, but we set it
2531      -      // explicitly here in case the default changes.
2532      -      // See runtime/compilationPolicy.*.
2533      -      FLAG_SET_CMDLINE(intx, CompilationPolicyChoice, 0);
2534      -
2535 2526        // Enable parallel GC and adaptive generation sizing
2536 2527        FLAG_SET_CMDLINE(bool, UseParallelGC, true);
2537 2528        FLAG_SET_DEFAULT(ParallelGCThreads,
2538 2529                         Abstract_VM_Version::parallel_worker_threads());
2539 2530  
2540 2531        // Encourage steady state memory management
2541 2532        FLAG_SET_CMDLINE(uintx, ThresholdTolerance, 100);
2542 2533  
2543 2534        // This appears to improve mutator locality
2544 2535        FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
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